1.Peering into the Abyss of Time

1.Peering into the Abyss of Time - Peering into the Abyss...

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Peering into the Abyss of Time - A fossil record consists of all the fossils that have been found and described in the scientific literature. - A geological time scale is a sequence of eons epochs and periods - Earliest signs of life appear 3.4-3.8 billion years ago 27.2 Fossil Record Fossils are formed by organisms that fall into areas of low decomposition such as below the water line or the bottom of a swamp. Then either a cast of the organism is created if it decomposes after being buried or if it decomposes really slowly minerals can gradually infiltrate the interior of cells and harden into stone to create permineralized fossils Life’s Time line: Precambrain 4.6BYA – 542 MYA, life was exclusively unicellular for most of Earth’s history and Oxygen was virtually absent from oceans and atmosphere for almost 2 billion years after the origin of life. From 542 MYA to Present is called the Phanerozoic eon.
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